For cases like IPv6 addresses, having a means to supply tracing
predicates for fields with more than 8 bytes would be convenient.
This series provides a simple way to support this by allowing
simple ==, != memory comparison with the predicate supplied when
the size of the field exceeds 8 bytes. For example, to trace
::1, the predicate
"dst == 0x00000000000000000000000000000001"
..could be used. Patch 1 implements this.
As a convenience, support for IPv4, IPv6 and MAC addresses are
also included; patches 2-4 cover these and allow simpler
comparisons which do not require getting the exact number of
bytes right; for exmaple
"dst == ::1"
"src != 127.0.0.1"
"mac_addr == ab:cd:ef:01:23:45"
Patch 5 adds tests for existing and new filter predicates, and patch 6
documents the fact that for the various addresses supported and
the >8 byte memory comparison. only == and != are supported.
Changes since v1 [1]:
- added support for IPv4, IPv6 and MAC addresses (patches 2-4)
(Masami and Steven)
- added selftests for IPv4, IPv6 and MAC addresses and updated
docs accordingly (patches 5,6)
Changes since RFC [2]:
- originally a fix was intermixed with the new functionality as
patch 1 in series [2]; the fix landed separately
- small tweaks to how filter predicates are defined via fn_num as
opposed to via fn directly
[1] https://lore.kernel.org/linux-trace-kernel/1682414197-13173-1-git-send-email-alan.maguire@xxxxxxxxxx/
[22] https://lore.kernel.org/lkml/1659910883-18223-1-git-send-email-alan.maguire@xxxxxxxxxx/
Alan Maguire (6):
tracing: support > 8 byte array filter predicates
tracing: support IPv4 address filter predicate
tracing: support IPv6 filter predicates
tracing: support MAC address filter predicates
selftests/ftrace: add test coverage for filter predicates
tracing: document IPv4, IPv6, MAC address and > 8 byte numeric
filtering support
Documentation/trace/events.rst | 21 +++
kernel/trace/trace_events_filter.c | 164 +++++++++++++++++-
.../selftests/ftrace/test.d/event/filter.tc | 91 ++++++++++
3 files changed, 275 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/ftrace/test.d/event/filter.tc
--
2.31.1
